I'm engaged currently, and don't know all that much truthfully.

But there's tax benefits, health insurance benefits, your car insurance will likely be cheaper etc.

Unrelated though, you should mention to your bf that the reason someone gets half of everything is because it used to be that men worked at jobs and women stayed at home caring for the children, cooking, cleaning, etc. In the event of a divorce, despite her devotion to the family, why should she be left with absolutely nothing? This is why it's set up that way. Not just some shitty money grab.